As is known, roller skis are items used on roads which generally replace Cross Country skis, and make it possible to exercise during summer or in any other circumstance in which snow tracks are not available.
Roller skis generally comprise a pair of elongated bodies that the user applies to his/her feet with suitable bindings and are provided with wheels for moving on the ground, thus imitating the sliding movement of skis on snow.
In particular, roller skis are generally provided with bindings similar to those used for snow skis, so that they can be used with a technique very similar to that used for snow skis.
As is known, snow skis, and in particular Cross Country skis, are generally braked using the so-called “snowplough” technique, which consists in turning the points of one or both skis inwards, in order to form a “V” converging in the skier's advance direction.
In this way, the skis are incident on each other and on the advance direction, in order to exploit the friction of their edges with snow.
This technique allows the skier to brake while keeping his/her feet resting on the skis, in such a way as to distribute his/her weight on the feet soles and thus maintain a good balance and a good control of the skis.
As regards the roller skis of known types, they pose the drawback that they cannot be braked by means of the above mentioned snowplough technique.
In fact, due to the high friction between the wheels and the ground, it is not possible to place the roller skis incident to the advance direction without immediately crossing them, which inevitably leads to a fall.
In order to overcome the above mentioned drawback, braking devices for roller skis are known, which comprise braking calipers associated with the wheels and operated by means of levers seized by the user.